This invention relates to a system and method for providing a record of the flight performance of an aircraft and engine performance, and more particularly, to a spread spectrum ground link-based aircraft data communication system that downloads not only engine data during initial take-off, but also flight performance data after the aircraft has landed.
A great amount of mechanical stress is placed on jet engines and their associated components during initial take-off. Some jet engine components and processes are now controlled through the well known engine air flow FADEC control system, which may include the sensing and control of core compartment bleeding, sump pressurization, sump venting, active clearance control, draining, and low pressure and high pressure recoup. In other jet engine designs, other engine sensors sense various associated components.
During initial take-off, the pilot observes many cockpit meters and observes engine performance. Based upon his analysis of the observed meters and his overall experience, the pilot may make an emergency landing or continue his flight to the destination even if he believes minor engine problems are occurring during initial take-off or in flight. If this engine data, such as that type of data contained through the engineer flow FADEC control and other sensors could be initialized initially during take-off, both onboard and on-ground, such as by a ground crew or automatic server located on the ground, better control over the engine could be exerted. Additionally, such information obtained during initial take-off could be used to determine maintenance schedules. Any immediate maintenance could be scheduled when the aircraft landed at its destination.
In copending patent application Ser. No. 08/557,269, filed Nov. 14, 1995, and entitled, xe2x80x9cWIRELESS, FREQUENCY-AGILE SPREAD SPECTRUM GROUND LINK-BASED AIRCRAFT DATA COMMUNICATION SYSTEM,xe2x80x9d (U.S. Pat. No. 6,047,165 issued Apr. 4, 2000) the disclosure which is hereby incorporated by reference in its entirety, a ground data link system provides a wireless mechanism for transferring data files to and from aircraft while the aircraft is on the ground at ground data link equipped airports. Flight performance data representative of aircraft flight performance is * obtained during flight of the aircraft and stored in a, data store. After the aircraft lands at the airport, the data is downloaded to an airport based spread spectrum receiver that could be part of an airport based server. Although the flight performance data is collected during flight, the spread spectrum transceiver could be used for downloading data initially at take-off.
It is therefore an object of the present invention to use a wireless spread spectrum ground link-based aircraft data communication system for downloading engine data initially during take-off.
In accordance with the present invention, the system provides a record of the flight performance of an aircraft and the record of engine data that is downloaded during initial take-off. In accordance with the present invention, a plurality of sensors are positioned on the aircraft for sensing engine conditions and generating engine data relating to the operation of the engine during at least initial take-off. A ground data link unit is positioned within the aircraft and operatively connected to the plurality of sensors for receiving the engine data. A central processing unit of the ground data link unit can receive the engine data and process the data for further downloading or initial determination of engine problems. The ground data link unit includes a data store operative to accumulate and store flight performance data during flight of the aircraft. The data store can also accumulate and store engine data received from the plurality of sensors.
A spread spectrum transceiver is coupled to the data store and includes a transmitter that is operative after the aircraft completes its flight and lands at an airport to download the flight performance data that has been accumulated and stored by the data store during flight over a spread spectrum communication signal. The spread spectrum transceiver also receives the engine data and is operative to download the engine data upon initial take-off over a spread spectrum communication signal. The airport based spread spectrum receiver receives the spread spectrum communication signal from the aircraft upon initial take-off and demodulates the spread spectrum communication signal to obtain the engine data. The airport based spread spectrum receiver receives flight performance data that has been stored and downloaded from a ground data link unit after an aircraft has landed at the airport.
In one aspect of the present invention, the data store of the ground data link unit is operative to store engine data to be accumulated during flight of the aircraft and then downloaded upon landing at the destination airport. The system also includes a FADEC engine control system. The sensors are operatively connected to the FADEC engine control system. The sensors are positioned to sense at least one of the core compartment bleeding, sump pressurization, sump venting, active clearance control, and low pressure and high pressure recoup. The sensors can also be positioned to sense at least one of oil pressure, oil temperature, fuel flow and engine hydraulics.
In still another aspect of the present invention, a plurality of sensors can be located throughout the aircraft for sensing routine aircraft conditions and generating parametric data such as received by a flight data recorder representative of the aircraft flight performance during flight of the aircraft. The system can include a multiplexer connected to the plurality of sensors and the ground data link unit for receiving the parametric data and multiplexing the parametric data for delivery to the ground data link unit.
In still another aspect of the present invention, an airport based server is connected to the airport based spread spectrum receiver for receiving the engine data for further processing of the engine data. A remote flight operations center operatively coupled to the airport based spread spectrum receiver for receiving and processing any flight performance data downloaded from the aircraft. The spread spectrum communication signal can comprise a direct sequence spread spectrum signal and a signal within the S band. It can also comprise a signal within the range of about 2.4 to about 2.5 GHZ. The data store of the ground data link unit can further comprise means for compressing the flight performance data during the flight of the aircraft. The emitted power of the spread spectrum communication signal can be about one watt.
In a method aspect of the present invention, engine data is collected within the ground data link unit during initial take-off of an aircraft from an airport. The method comprises the step of downloading the engine data that has been collected during initial take-off over a spread spectrum communication signal to an airport based spread spectrum receiver. The method also comprises the step of demodulating within the airport based spread spectrum receiver the spread spectrum communication signal to obtain the engine data. Demodulated data is forwarded to a server for further processing. The method further comprises the step of collecting data within the ground data link unit on the flight performance of the aircraft during flight of the aircraft. The flight performance data is accumulated and stored within a data store of the ground data link unit. After the aircraft lands in an airport at completion of its flight, the flight performance data is downloaded over a spread spectrum communication signal to an airport based spread spectrum receiver. The receiver demodulates the receive spread spectrum signal to obtain the flight performance data.
In still another aspect of the present invention, the engine data is processed within an airport based server that is connected to the airport based spread spectrum receiver. The spread spectrum communication signal includes a direct sequence spread spectrum signal that can comprise a signal within the S band. The spread spectrum communication signal comprises a signal within the range of about 2.4 to about 2.5 GHz.